#include<stdio.h>
#include<stdbool.h>
int main()
{
    //定义一个类型，申明并初始化化
    enum Weekday{Monday,Tuesday,Wednesday,Thursday,Friday,Saturday,Sunday}today = Monday,tomorrow = today +1;
    printf("%d\n",tomorrow);
     
     _Bool valid =1;
      bool valid2 =1;
}